It has been proposed to blend a mica-containing pigment in a so-called metallic paint composition to be used in the glossy finish on steel products and other metal products (especially automobile bodies).
For this type of coating, the automobile industry employs the 2-coat-1-bake method. This method comprises coating with a metallic paint composition, and then, without baking, coating with a clear paint, and finally baking.
Recently, a water base coating material with a metal-like gloss which contains mica foil coated with titanium dioxide (Japanese unexamined patent publication (Tokkai) Sho-109566) has been proposed and is receiving attention. However, when a mica-containing pigment is blended in a water base paint, the dispersion of three pigment is poor and aggregation and such occurs. Therefore, if this is used in a metallic coating followed by application of a clear paint, the appearance is poor, and thus it cannot be used in automobile coatings.
Also, it has been found that the water resistance of the resulting paint film is poor when metallic coating is conducted using this type of water base paint.
Therefore, a water base paint is desired which: is a water base paint composition containing a mica-containing pigment(s); has good dispersion stability; can be used for the metallic coating of automobiles and such; gives a superior appearance; and does not cause deterioration of coating characteristics, particularly the water resistance and adhesion. The object of this invention is to provide a mica-containing pigment composition for such water base paints and a water base paint composition containing the mica-containing pigment, as well as a method for manufacturing same.